[PATCH v3 0/4] Add SBI FWFT extension support

[PATCH v3 0/4] Add SBI FWFT extension support

[Clément Léger]

This series adds support for SBI FWFT extension. FWFT extension is not
yet ratified but will be present in SBI V3.0 [1]. Current support can be
tested using kvm-unit-tests [2] using the following command:

$ qemu-system-riscv64 -s -M virt -cpu rv64 -nographic -serial mon:stdio?\
	-bios <opensbi_fwft>/build/platform/generic/firmware/fw_jump.bin
	-kernel <kvm-unit-tests>/riscv/sbi_fwft.flat

Or with spike (with misaligned traps) using this one:

$ spike \
  --kernel /home/cleger/Dev/repos/kvm-unit-tests-fwft/riscv/sbi_fwft.flat \
  /home/cleger/Dev/repos/opensbi_fwft/build/platform/generic/firmware/fw_jump.elf

Link: https://lists.riscv.org/g/tech-prs/message/924 [1]
Link: https://github.com/clementleger/kvm-unit-tests/tree/dev/cleger/fwft [2]

---
V3:
 - Fixed saving of medeleg (was hedeleg)
 - Rebased on master

V2:
 - Rebased on top of Yong-Xuan Wang svadu/svade series
 - Updated wrt latest FWFT spec (removed software check exception deleg)

Cl?ment L?ger (4):
  lib: sbi: add support for firmware features extension
  lib: sbi: fwft: add support for SBI_FWFT_MISALIGNED_EXC_DELEG
  lib: sbi: fwft: add support for SBI_FWFT_PTE_AD_HW_UPDATING
  lib: sbi: implement SBI FWFT extension

 include/sbi/sbi_ecall_interface.h |  27 +++
 include/sbi/sbi_fwft.h            |  23 +++
 lib/sbi/Kconfig                   |   4 +
 lib/sbi/objects.mk                |   4 +
 lib/sbi/sbi_ecall_fwft.c          |  49 ++++++
 lib/sbi/sbi_fwft.c                | 262 ++++++++++++++++++++++++++++++
 lib/sbi/sbi_hsm.c                 |  15 ++
 lib/sbi/sbi_init.c                |  11 ++
 8 files changed, 395 insertions(+)
 create mode 100644 include/sbi/sbi_fwft.h
 create mode 100644 lib/sbi/sbi_ecall_fwft.c
 create mode 100644 lib/sbi/sbi_fwft.c

-- 
2.45.2

[PATCH v3 1/4] lib: sbi: add support for firmware features extension

[Clément Léger]

This extension allows the software running in supervisor mode to control
the behavior of various features of the SBI [1]. Implement the support
for such extension.

Link: https://lists.riscv.org/g/tech-prs/message/924 [1]
Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 include/sbi/sbi_ecall_interface.h |  27 +++++
 include/sbi/sbi_fwft.h            |  23 ++++
 lib/sbi/objects.mk                |   1 +
 lib/sbi/sbi_fwft.c                | 178 ++++++++++++++++++++++++++++++
 lib/sbi/sbi_init.c                |  11 ++
 5 files changed, 240 insertions(+)
 create mode 100644 include/sbi/sbi_fwft.h
 create mode 100644 lib/sbi/sbi_fwft.c

diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h
index 2600b66..e9a8167 100644
--- a/include/sbi/sbi_ecall_interface.h
+++ b/include/sbi/sbi_ecall_interface.h
@@ -34,6 +34,7 @@
 #define SBI_EXT_CPPC				0x43505043
 #define SBI_EXT_DBTR				0x44425452
 #define SBI_EXT_SSE				0x535345
+#define SBI_EXT_FWFT				0x46574654
 
 /* SBI function IDs for BASE extension*/
 #define SBI_EXT_BASE_GET_SPEC_VERSION		0x0
@@ -117,6 +118,32 @@
 #define SBI_EXT_DBTR_TRIGGER_ENABLE	0x6
 #define SBI_EXT_DBTR_TRIGGER_DISABLE	0x7
 
+/* SBI function IDs for FW feature extension */
+#define SBI_EXT_FWFT_SET		0x0
+#define SBI_EXT_FWFT_GET		0x1
+
+enum sbi_fwft_feature_t {
+	SBI_FWFT_MISALIGNED_EXC_DELEG		= 0x0,
+	SBI_FWFT_LANDING_PAD			= 0x1,
+	SBI_FWFT_SHADOW_STACK			= 0x2,
+	SBI_FWFT_DOUBLE_TRAP			= 0x3,
+	SBI_FWFT_PTE_AD_HW_UPDATING		= 0x4,
+	SBI_FWFT_LOCAL_RESERVED_START		= 0x5,
+	SBI_FWFT_LOCAL_RESERVED_END		= 0x3fffffff,
+	SBI_FWFT_LOCAL_PLATFORM_START		= 0x40000000,
+	SBI_FWFT_LOCAL_PLATFORM_END		= 0x7fffffff,
+
+	SBI_FWFT_GLOBAL_RESERVED_START		= 0x80000000,
+	SBI_FWFT_GLOBAL_RESERVED_END		= 0xbfffffff,
+	SBI_FWFT_GLOBAL_PLATFORM_START		= 0xc0000000,
+	SBI_FWFT_GLOBAL_PLATFORM_END		= 0xffffffff,
+};
+
+#define SBI_FWFT_GLOBAL_FEATURE_BIT		(1 << 31)
+#define SBI_FWFT_PLATFORM_FEATURE_BIT		(1 << 30)
+
+#define SBI_FWFT_SET_FLAG_LOCK			(1 << 0)
+
 /** General pmu event codes specified in SBI PMU extension */
 enum sbi_pmu_hw_generic_events_t {
 	SBI_PMU_HW_NO_EVENT			= 0,
diff --git a/include/sbi/sbi_fwft.h b/include/sbi/sbi_fwft.h
new file mode 100644
index 0000000..2148820
--- /dev/null
+++ b/include/sbi/sbi_fwft.h
@@ -0,0 +1,23 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2024 Rivos Inc.
+ *
+ * Authors:
+ *   Cl?ment L?ger <cleger@rivosinc.com>
+ */
+
+#ifndef __SBI_FW_FEATURE_H__
+#define __SBI_FW_FEATURE_H__
+
+#include <sbi/sbi_ecall_interface.h>
+
+struct sbi_scratch;
+
+int sbi_fwft_set(enum sbi_fwft_feature_t feature, unsigned long value,
+		 unsigned long flags);
+int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val);
+
+int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot);
+
+#endif
diff --git a/lib/sbi/objects.mk b/lib/sbi/objects.mk
index b1c4a50..221e72c 100644
--- a/lib/sbi/objects.mk
+++ b/lib/sbi/objects.mk
@@ -65,6 +65,7 @@ libsbi-objs-y += sbi_domain_context.o
 libsbi-objs-y += sbi_domain.o
 libsbi-objs-y += sbi_emulate_csr.o
 libsbi-objs-y += sbi_fifo.o
+libsbi-objs-y += sbi_fwft.o
 libsbi-objs-y += sbi_hart.o
 libsbi-objs-y += sbi_heap.o
 libsbi-objs-y += sbi_math.o
diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
new file mode 100644
index 0000000..b302b5d
--- /dev/null
+++ b/lib/sbi/sbi_fwft.c
@@ -0,0 +1,178 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2024 Rivos Inc.
+ *
+ * Authors:
+ *   Cl?ment L?ger <cleger@rivosinc.com>
+ */
+
+#include <sbi/sbi_console.h>
+#include <sbi/sbi_bitmap.h>
+#include <sbi/sbi_ecall_interface.h>
+#include <sbi/sbi_error.h>
+#include <sbi/sbi_hart.h>
+#include <sbi/sbi_heap.h>
+#include <sbi/sbi_scratch.h>
+#include <sbi/sbi_string.h>
+#include <sbi/sbi_types.h>
+
+#include <sbi/riscv_asm.h>
+#include <sbi/riscv_encoding.h>
+
+/** Offset of pointer to FWFT HART state in scratch space */
+static unsigned long fwft_ptr_offset;
+
+#define fwft_get_hart_state_ptr(__scratch)				\
+	sbi_scratch_read_type((__scratch), void *, fwft_ptr_offset)
+
+#define fwft_thishart_state_ptr()					\
+	fwft_get_hart_state_ptr(sbi_scratch_thishart_ptr())
+
+#define fwft_set_hart_state_ptr(__scratch, __phs)			\
+	sbi_scratch_write_type((__scratch), void *, fwft_ptr_offset, (__phs))
+
+struct fwft_config;
+
+struct fwft_feature {
+	enum sbi_fwft_feature_t id;
+	int (*supported)(struct fwft_config *conf);
+	int (*set)(struct fwft_config *conf, unsigned long value);
+	int (*get)(struct fwft_config *conf, unsigned long *value);
+};
+
+struct fwft_config {
+	const struct fwft_feature *feature;
+	unsigned long flags;
+};
+
+struct fwft_hart_state {
+	unsigned int config_count;
+	struct fwft_config configs[];
+};
+
+static const unsigned long fwft_defined_features[] = {
+	SBI_FWFT_MISALIGNED_EXC_DELEG,
+	SBI_FWFT_LANDING_PAD,
+	SBI_FWFT_SHADOW_STACK,
+	SBI_FWFT_DOUBLE_TRAP,
+	SBI_FWFT_PTE_AD_HW_UPDATING,
+};
+
+static bool fwft_is_defined_feature(enum sbi_fwft_feature_t feature)
+{
+	int i;
+
+	for (i = 0; i < array_size(fwft_defined_features); i++) {
+		if (fwft_defined_features[i] == feature)
+			return true;
+	}
+
+	return false;
+}
+
+static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
+{
+	int i;
+	struct fwft_hart_state *fhs = fwft_thishart_state_ptr();
+
+	if (feature & SBI_FWFT_GLOBAL_FEATURE_BIT)
+		return NULL;
+
+	for (i = 0; i < fhs->config_count; i++){
+		if (feature == fhs->configs[i].feature->id)
+			return &fhs->configs[i];
+	}
+
+	return NULL;
+}
+
+static int fwft_get_feature(enum sbi_fwft_feature_t feature,
+			    struct fwft_config **conf)
+{
+	int ret;
+	struct fwft_config *tconf;
+
+	tconf = get_feature_config(feature);
+	if (!tconf) {
+		if (fwft_is_defined_feature(feature))
+			return SBI_ENOTSUPP;
+
+		return SBI_EDENIED;
+	}
+
+	if (tconf->feature->supported) {
+		ret = tconf->feature->supported(tconf);
+		if (ret)
+			return ret;
+	}
+	*conf = tconf;
+
+	return SBI_SUCCESS;
+}
+
+int sbi_fwft_set(enum sbi_fwft_feature_t feature, unsigned long value,
+		 unsigned long flags)
+{
+	int ret;
+	struct fwft_config *conf;
+
+	ret = fwft_get_feature(feature, &conf);
+	if (ret)
+		return ret;
+
+	if ((flags & ~SBI_FWFT_SET_FLAG_LOCK) != 0)
+		return SBI_ERR_INVALID_PARAM;
+
+	if (conf->flags & SBI_FWFT_SET_FLAG_LOCK)
+		return SBI_EDENIED;
+
+	ret = conf->feature->set(conf, value);
+	if (ret)
+		return ret;
+
+	conf->flags = flags;
+
+	return SBI_OK;
+}
+
+int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val)
+{
+	int ret;
+	struct fwft_config *conf;
+
+	ret = fwft_get_feature(feature, &conf);
+	if (ret)
+		return ret;
+
+	return conf->feature->get(conf, out_val);
+}
+
+static const struct fwft_feature features[] = {};
+
+int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
+{
+	int i;
+	struct fwft_hart_state *fhs;
+
+	if (cold_boot) {
+		fwft_ptr_offset = sbi_scratch_alloc_type_offset(void *);
+		if (!fwft_ptr_offset)
+			return SBI_ENOMEM;
+	}
+
+	fhs = fwft_get_hart_state_ptr(scratch);
+	if (!fhs) {
+		fhs = sbi_zalloc(sizeof(fhs) + array_size(features) * sizeof(struct fwft_config));
+		if (!fhs)
+			return SBI_ENOMEM;
+
+		fhs->config_count = array_size(features);
+		for (i = 0; i < array_size(features); i++)
+			fhs->configs[i].feature = &features[i];
+
+		fwft_set_hart_state_ptr(scratch, fhs);
+	}
+
+	return 0;
+}
diff --git a/lib/sbi/sbi_init.c b/lib/sbi/sbi_init.c
index 389172a..0f9e14c 100644
--- a/lib/sbi/sbi_init.c
+++ b/lib/sbi/sbi_init.c
@@ -14,6 +14,7 @@
 #include <sbi/sbi_cppc.h>
 #include <sbi/sbi_domain.h>
 #include <sbi/sbi_ecall.h>
+#include <sbi/sbi_fwft.h>
 #include <sbi/sbi_hart.h>
 #include <sbi/sbi_hartmask.h>
 #include <sbi/sbi_heap.h>
@@ -308,6 +309,12 @@ static void __noreturn init_coldboot(struct sbi_scratch *scratch, u32 hartid)
 		sbi_hart_hang();
 	}
 
+	rc = sbi_fwft_init(scratch, true);
+	if (rc) {
+		sbi_printf("%s: fwft init failed (error %d)\n", __func__, rc);
+		sbi_hart_hang();
+	}
+
 	/*
 	 * Note: Finalize domains after HSM initialization so that we
 	 * can startup non-root domains.
@@ -423,6 +430,10 @@ static void __noreturn init_warm_startup(struct sbi_scratch *scratch,
 	if (rc)
 		sbi_hart_hang();
 
+	rc = sbi_fwft_init(scratch, false);
+	if (rc)
+		sbi_hart_hang();
+
 	rc = sbi_platform_final_init(plat, false);
 	if (rc)
 		sbi_hart_hang();
-- 
2.45.2

[PATCH v3 2/4] lib: sbi: fwft: add support for SBI_FWFT_MISALIGNED_EXC_DELEG

[Clément Léger]

Add support for SBI_FWFT_MISALIGNED_EXC_DELEG withing FWFT support. This
support allows to delegate misaligned accesses traps.

Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 lib/sbi/sbi_fwft.c | 39 ++++++++++++++++++++++++++++++++++++++-
 lib/sbi/sbi_hsm.c  |  3 +++
 2 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
index b302b5d..289a344 100644
--- a/lib/sbi/sbi_fwft.c
+++ b/lib/sbi/sbi_fwft.c
@@ -32,6 +32,8 @@ static unsigned long fwft_ptr_offset;
 #define fwft_set_hart_state_ptr(__scratch, __phs)			\
 	sbi_scratch_write_type((__scratch), void *, fwft_ptr_offset, (__phs))
 
+#define MIS_DELEG (1UL << CAUSE_MISALIGNED_LOAD | 1UL << CAUSE_MISALIGNED_STORE)
+
 struct fwft_config;
 
 struct fwft_feature {
@@ -71,6 +73,33 @@ static bool fwft_is_defined_feature(enum sbi_fwft_feature_t feature)
 	return false;
 }
 
+static int fwft_misaligned_delegation_supported(struct fwft_config *conf)
+{
+	if (!misa_extension('S'))
+		return SBI_ENOTSUPP;
+
+	return SBI_OK;
+}
+
+static int fwft_set_misaligned_delegation(struct fwft_config *conf,
+					 unsigned long value)
+{
+	if (value)
+		csr_set(CSR_MEDELEG, MIS_DELEG);
+	else
+		csr_clear(CSR_MEDELEG, MIS_DELEG);
+
+	return SBI_OK;
+}
+
+static int fwft_get_misaligned_delegation(struct fwft_config *conf,
+					 unsigned long *value)
+{
+	*value = (csr_read(CSR_MEDELEG) & MIS_DELEG) != 0;
+
+	return SBI_OK;
+}
+
 static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
 {
 	int i;
@@ -148,7 +177,15 @@ int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val)
 	return conf->feature->get(conf, out_val);
 }
 
-static const struct fwft_feature features[] = {};
+static const struct fwft_feature features[] =
+{
+	{
+		.id = SBI_FWFT_MISALIGNED_EXC_DELEG,
+		.supported = fwft_misaligned_delegation_supported,
+		.set = fwft_set_misaligned_delegation,
+		.get = fwft_get_misaligned_delegation,
+	},
+};
 
 int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
 {
diff --git a/lib/sbi/sbi_hsm.c b/lib/sbi/sbi_hsm.c
index be48d64..2b23e13 100644
--- a/lib/sbi/sbi_hsm.c
+++ b/lib/sbi/sbi_hsm.c
@@ -44,6 +44,7 @@ struct sbi_hsm_data {
 	unsigned long suspend_type;
 	unsigned long saved_mie;
 	unsigned long saved_mip;
+	unsigned long saved_medeleg;
 	atomic_t start_ticket;
 };
 
@@ -417,6 +418,7 @@ void __sbi_hsm_suspend_non_ret_save(struct sbi_scratch *scratch)
 
 	hdata->saved_mie = csr_read(CSR_MIE);
 	hdata->saved_mip = csr_read(CSR_MIP) & (MIP_SSIP | MIP_STIP);
+	hdata->saved_medeleg = csr_read(CSR_MEDELEG);
 }
 
 static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
@@ -424,6 +426,7 @@ static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
 	struct sbi_hsm_data *hdata = sbi_scratch_offset_ptr(scratch,
 							    hart_data_offset);
 
+	csr_write(CSR_MEDELEG, hdata->saved_medeleg);
 	csr_write(CSR_MIE, hdata->saved_mie);
 	csr_set(CSR_MIP, (hdata->saved_mip & (MIP_SSIP | MIP_STIP)));
 }
-- 
2.45.2

[PATCH v3 3/4] lib: sbi: fwft: add support for SBI_FWFT_PTE_AD_HW_UPDATING

[Clément Léger]

Add support for SBI_FWFT_PTE_AD_HW_UPDATING based on SVADU presence.

Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 lib/sbi/sbi_fwft.c | 47 ++++++++++++++++++++++++++++++++++++++++++++++
 lib/sbi/sbi_hsm.c  | 12 ++++++++++++
 2 files changed, 59 insertions(+)

diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
index 289a344..aff087f 100644
--- a/lib/sbi/sbi_fwft.c
+++ b/lib/sbi/sbi_fwft.c
@@ -100,6 +100,47 @@ static int fwft_get_misaligned_delegation(struct fwft_config *conf,
 	return SBI_OK;
 }
 
+static int fwft_adue_supported(struct fwft_config *conf)
+{
+	if (!sbi_hart_has_extension(sbi_scratch_thishart_ptr(),
+				    SBI_HART_EXT_SVADU))
+		return SBI_ENOTSUPP;
+
+	return SBI_OK;
+}
+
+static int fwft_set_adue(struct fwft_config *conf, unsigned long value)
+{
+	if (value)
+#if __riscv_xlen == 32
+		csr_set(CSR_MENVCFGH, ENVCFG_ADUE >> 32);
+#else
+		csr_set(CSR_MENVCFG, ENVCFG_ADUE);
+#endif
+	else
+#if __riscv_xlen == 32
+		csr_clear(CSR_MENVCFGH, ENVCFG_ADUE >> 32);
+#else
+		csr_clear(CSR_MENVCFG, ENVCFG_ADUE);
+#endif
+
+	return SBI_OK;
+}
+
+static int fwft_get_adue(struct fwft_config *conf, unsigned long *value)
+{
+	unsigned long cfg;
+
+#if __riscv_xlen == 32
+	cfg = csr_read(CSR_MENVCFGH) & (ENVCFG_ADUE >> 32);
+#else
+	cfg = csr_read(CSR_MENVCFG) & ENVCFG_ADUE;
+#endif
+	*value = cfg != 0;
+
+	return SBI_OK;
+}
+
 static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
 {
 	int i;
@@ -185,6 +226,12 @@ static const struct fwft_feature features[] =
 		.set = fwft_set_misaligned_delegation,
 		.get = fwft_get_misaligned_delegation,
 	},
+	{
+		.id = SBI_FWFT_PTE_AD_HW_UPDATING,
+		.supported = fwft_adue_supported,
+		.set = fwft_set_adue,
+		.get = fwft_get_adue,
+	},
 };
 
 int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
diff --git a/lib/sbi/sbi_hsm.c b/lib/sbi/sbi_hsm.c
index 2b23e13..7e32af3 100644
--- a/lib/sbi/sbi_hsm.c
+++ b/lib/sbi/sbi_hsm.c
@@ -45,6 +45,10 @@ struct sbi_hsm_data {
 	unsigned long saved_mie;
 	unsigned long saved_mip;
 	unsigned long saved_medeleg;
+	unsigned long saved_menvcfg;
+#if __riscv_xlen == 32
+	unsigned long saved_menvcfgh;
+#endif
 	atomic_t start_ticket;
 };
 
@@ -419,6 +423,10 @@ void __sbi_hsm_suspend_non_ret_save(struct sbi_scratch *scratch)
 	hdata->saved_mie = csr_read(CSR_MIE);
 	hdata->saved_mip = csr_read(CSR_MIP) & (MIP_SSIP | MIP_STIP);
 	hdata->saved_medeleg = csr_read(CSR_MEDELEG);
+#if __riscv_xlen == 32
+	hdata->saved_menvcfgh = csr_read(CSR_MENVCFGH);
+#endif
+	hdata->saved_menvcfg = csr_read(CSR_MENVCFG);
 }
 
 static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
@@ -426,6 +434,10 @@ static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
 	struct sbi_hsm_data *hdata = sbi_scratch_offset_ptr(scratch,
 							    hart_data_offset);
 
+	csr_write(CSR_MENVCFG, hdata->saved_menvcfg);
+#if __riscv_xlen == 32
+	csr_write(CSR_MENVCFGH, hdata->saved_menvcfgh);
+#endif
 	csr_write(CSR_MEDELEG, hdata->saved_medeleg);
 	csr_write(CSR_MIE, hdata->saved_mie);
 	csr_set(CSR_MIP, (hdata->saved_mip & (MIP_SSIP | MIP_STIP)));
-- 
2.45.2

[PATCH v3 4/4] lib: sbi: implement SBI FWFT extension

[Clément Léger]

The SBI FWFT extension defines a set of function that can be called to
control the configuration of some platform features (misaligned
trap delegation, etc). This patch implements sbi_fwft_set() and
sbi_fwft_get() as defined in the specification [1].

Link: https://lists.riscv.org/g/tech-prs/message/924 [1]
Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
---
 lib/sbi/Kconfig          |  4 ++++
 lib/sbi/objects.mk       |  3 +++
 lib/sbi/sbi_ecall_fwft.c | 49 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 56 insertions(+)
 create mode 100644 lib/sbi/sbi_ecall_fwft.c

diff --git a/lib/sbi/Kconfig b/lib/sbi/Kconfig
index cc8e031..6cf54ce 100644
--- a/lib/sbi/Kconfig
+++ b/lib/sbi/Kconfig
@@ -38,6 +38,10 @@ config SBI_ECALL_CPPC
 	bool "CPPC extension"
 	default y
 
+config SBI_ECALL_FWFT
+	bool "Firmware Feature extension"
+	default y
+
 config SBI_ECALL_LEGACY
 	bool "SBI v0.1 legacy extensions"
 	default y
diff --git a/lib/sbi/objects.mk b/lib/sbi/objects.mk
index 221e72c..211abad 100644
--- a/lib/sbi/objects.mk
+++ b/lib/sbi/objects.mk
@@ -46,6 +46,9 @@ libsbi-objs-$(CONFIG_SBI_ECALL_DBCN) += sbi_ecall_dbcn.o
 carray-sbi_ecall_exts-$(CONFIG_SBI_ECALL_CPPC) += ecall_cppc
 libsbi-objs-$(CONFIG_SBI_ECALL_CPPC) += sbi_ecall_cppc.o
 
+carray-sbi_ecall_exts-$(CONFIG_SBI_ECALL_FWFT) += ecall_fwft
+libsbi-objs-$(CONFIG_SBI_ECALL_FWFT) += sbi_ecall_fwft.o
+
 carray-sbi_ecall_exts-$(CONFIG_SBI_ECALL_LEGACY) += ecall_legacy
 libsbi-objs-$(CONFIG_SBI_ECALL_LEGACY) += sbi_ecall_legacy.o
 
diff --git a/lib/sbi/sbi_ecall_fwft.c b/lib/sbi/sbi_ecall_fwft.c
new file mode 100644
index 0000000..267cbab
--- /dev/null
+++ b/lib/sbi/sbi_ecall_fwft.c
@@ -0,0 +1,49 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2024 Rivos Inc.
+ *
+ * Authors:
+ *   Cl?ment L?ger <cleger@rivosinc.com>
+ */
+
+#include <sbi/sbi_ecall.h>
+#include <sbi/sbi_ecall_interface.h>
+#include <sbi/sbi_error.h>
+#include <sbi/sbi_fwft.h>
+#include <sbi/sbi_trap.h>
+
+static int sbi_ecall_fwft_handler(unsigned long extid, unsigned long funcid,
+				 struct sbi_trap_regs *regs,
+				 struct sbi_ecall_return *out)
+{
+	int ret = 0;
+
+	switch (funcid) {
+	case SBI_EXT_FWFT_SET:
+		ret = sbi_fwft_set(regs->a0, regs->a1, regs->a2);
+		break;
+	case SBI_EXT_FWFT_GET:
+		ret = sbi_fwft_get(regs->a0, &out->value);
+		break;
+	default:
+		ret = SBI_ENOTSUPP;
+		break;
+	}
+
+	return ret;
+}
+
+struct sbi_ecall_extension ecall_fwft;
+
+static int sbi_ecall_fwft_register_extensions(void)
+{
+	return sbi_ecall_register_extension(&ecall_fwft);
+}
+
+struct sbi_ecall_extension ecall_fwft = {
+	.extid_start = SBI_EXT_FWFT,
+	.extid_end = SBI_EXT_FWFT,
+	.register_extensions = sbi_ecall_fwft_register_extensions,
+	.handle = sbi_ecall_fwft_handler,
+};
-- 
2.45.2

[PATCH v3 1/4] lib: sbi: add support for firmware features extension

[Anup Patel]

On Wed, Jun 19, 2024 at 3:13?PM Cl?ment L?ger <cleger@rivosinc.com> wrote:
>
> This extension allows the software running in supervisor mode to control
> the behavior of various features of the SBI [1]. Implement the support
> for such extension.
>
> Link: https://lists.riscv.org/g/tech-prs/message/924 [1]
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>

I had already reviewed the previous revision of this patch.

Reviewed-by: Anup Patel <anup@brainfault.org>

Applied this patch to the riscv/opensbi repo.

Thanks,
Anup

> ---
>  include/sbi/sbi_ecall_interface.h |  27 +++++
>  include/sbi/sbi_fwft.h            |  23 ++++
>  lib/sbi/objects.mk                |   1 +
>  lib/sbi/sbi_fwft.c                | 178 ++++++++++++++++++++++++++++++
>  lib/sbi/sbi_init.c                |  11 ++
>  5 files changed, 240 insertions(+)
>  create mode 100644 include/sbi/sbi_fwft.h
>  create mode 100644 lib/sbi/sbi_fwft.c
>
> diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h
> index 2600b66..e9a8167 100644
> --- a/include/sbi/sbi_ecall_interface.h
> +++ b/include/sbi/sbi_ecall_interface.h
> @@ -34,6 +34,7 @@
>  #define SBI_EXT_CPPC                           0x43505043
>  #define SBI_EXT_DBTR                           0x44425452
>  #define SBI_EXT_SSE                            0x535345
> +#define SBI_EXT_FWFT                           0x46574654
>
>  /* SBI function IDs for BASE extension*/
>  #define SBI_EXT_BASE_GET_SPEC_VERSION          0x0
> @@ -117,6 +118,32 @@
>  #define SBI_EXT_DBTR_TRIGGER_ENABLE    0x6
>  #define SBI_EXT_DBTR_TRIGGER_DISABLE   0x7
>
> +/* SBI function IDs for FW feature extension */
> +#define SBI_EXT_FWFT_SET               0x0
> +#define SBI_EXT_FWFT_GET               0x1
> +
> +enum sbi_fwft_feature_t {
> +       SBI_FWFT_MISALIGNED_EXC_DELEG           = 0x0,
> +       SBI_FWFT_LANDING_PAD                    = 0x1,
> +       SBI_FWFT_SHADOW_STACK                   = 0x2,
> +       SBI_FWFT_DOUBLE_TRAP                    = 0x3,
> +       SBI_FWFT_PTE_AD_HW_UPDATING             = 0x4,
> +       SBI_FWFT_LOCAL_RESERVED_START           = 0x5,
> +       SBI_FWFT_LOCAL_RESERVED_END             = 0x3fffffff,
> +       SBI_FWFT_LOCAL_PLATFORM_START           = 0x40000000,
> +       SBI_FWFT_LOCAL_PLATFORM_END             = 0x7fffffff,
> +
> +       SBI_FWFT_GLOBAL_RESERVED_START          = 0x80000000,
> +       SBI_FWFT_GLOBAL_RESERVED_END            = 0xbfffffff,
> +       SBI_FWFT_GLOBAL_PLATFORM_START          = 0xc0000000,
> +       SBI_FWFT_GLOBAL_PLATFORM_END            = 0xffffffff,
> +};
> +
> +#define SBI_FWFT_GLOBAL_FEATURE_BIT            (1 << 31)
> +#define SBI_FWFT_PLATFORM_FEATURE_BIT          (1 << 30)
> +
> +#define SBI_FWFT_SET_FLAG_LOCK                 (1 << 0)
> +
>  /** General pmu event codes specified in SBI PMU extension */
>  enum sbi_pmu_hw_generic_events_t {
>         SBI_PMU_HW_NO_EVENT                     = 0,
> diff --git a/include/sbi/sbi_fwft.h b/include/sbi/sbi_fwft.h
> new file mode 100644
> index 0000000..2148820
> --- /dev/null
> +++ b/include/sbi/sbi_fwft.h
> @@ -0,0 +1,23 @@
> +/*
> + * SPDX-License-Identifier: BSD-2-Clause
> + *
> + * Copyright (c) 2024 Rivos Inc.
> + *
> + * Authors:
> + *   Cl?ment L?ger <cleger@rivosinc.com>
> + */
> +
> +#ifndef __SBI_FW_FEATURE_H__
> +#define __SBI_FW_FEATURE_H__
> +
> +#include <sbi/sbi_ecall_interface.h>
> +
> +struct sbi_scratch;
> +
> +int sbi_fwft_set(enum sbi_fwft_feature_t feature, unsigned long value,
> +                unsigned long flags);
> +int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val);
> +
> +int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot);
> +
> +#endif
> diff --git a/lib/sbi/objects.mk b/lib/sbi/objects.mk
> index b1c4a50..221e72c 100644
> --- a/lib/sbi/objects.mk
> +++ b/lib/sbi/objects.mk
> @@ -65,6 +65,7 @@ libsbi-objs-y += sbi_domain_context.o
>  libsbi-objs-y += sbi_domain.o
>  libsbi-objs-y += sbi_emulate_csr.o
>  libsbi-objs-y += sbi_fifo.o
> +libsbi-objs-y += sbi_fwft.o
>  libsbi-objs-y += sbi_hart.o
>  libsbi-objs-y += sbi_heap.o
>  libsbi-objs-y += sbi_math.o
> diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
> new file mode 100644
> index 0000000..b302b5d
> --- /dev/null
> +++ b/lib/sbi/sbi_fwft.c
> @@ -0,0 +1,178 @@
> +/*
> + * SPDX-License-Identifier: BSD-2-Clause
> + *
> + * Copyright (c) 2024 Rivos Inc.
> + *
> + * Authors:
> + *   Cl?ment L?ger <cleger@rivosinc.com>
> + */
> +
> +#include <sbi/sbi_console.h>
> +#include <sbi/sbi_bitmap.h>
> +#include <sbi/sbi_ecall_interface.h>
> +#include <sbi/sbi_error.h>
> +#include <sbi/sbi_hart.h>
> +#include <sbi/sbi_heap.h>
> +#include <sbi/sbi_scratch.h>
> +#include <sbi/sbi_string.h>
> +#include <sbi/sbi_types.h>
> +
> +#include <sbi/riscv_asm.h>
> +#include <sbi/riscv_encoding.h>
> +
> +/** Offset of pointer to FWFT HART state in scratch space */
> +static unsigned long fwft_ptr_offset;
> +
> +#define fwft_get_hart_state_ptr(__scratch)                             \
> +       sbi_scratch_read_type((__scratch), void *, fwft_ptr_offset)
> +
> +#define fwft_thishart_state_ptr()                                      \
> +       fwft_get_hart_state_ptr(sbi_scratch_thishart_ptr())
> +
> +#define fwft_set_hart_state_ptr(__scratch, __phs)                      \
> +       sbi_scratch_write_type((__scratch), void *, fwft_ptr_offset, (__phs))
> +
> +struct fwft_config;
> +
> +struct fwft_feature {
> +       enum sbi_fwft_feature_t id;
> +       int (*supported)(struct fwft_config *conf);
> +       int (*set)(struct fwft_config *conf, unsigned long value);
> +       int (*get)(struct fwft_config *conf, unsigned long *value);
> +};
> +
> +struct fwft_config {
> +       const struct fwft_feature *feature;
> +       unsigned long flags;
> +};
> +
> +struct fwft_hart_state {
> +       unsigned int config_count;
> +       struct fwft_config configs[];
> +};
> +
> +static const unsigned long fwft_defined_features[] = {
> +       SBI_FWFT_MISALIGNED_EXC_DELEG,
> +       SBI_FWFT_LANDING_PAD,
> +       SBI_FWFT_SHADOW_STACK,
> +       SBI_FWFT_DOUBLE_TRAP,
> +       SBI_FWFT_PTE_AD_HW_UPDATING,
> +};
> +
> +static bool fwft_is_defined_feature(enum sbi_fwft_feature_t feature)
> +{
> +       int i;
> +
> +       for (i = 0; i < array_size(fwft_defined_features); i++) {
> +               if (fwft_defined_features[i] == feature)
> +                       return true;
> +       }
> +
> +       return false;
> +}
> +
> +static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
> +{
> +       int i;
> +       struct fwft_hart_state *fhs = fwft_thishart_state_ptr();
> +
> +       if (feature & SBI_FWFT_GLOBAL_FEATURE_BIT)
> +               return NULL;
> +
> +       for (i = 0; i < fhs->config_count; i++){
> +               if (feature == fhs->configs[i].feature->id)
> +                       return &fhs->configs[i];
> +       }
> +
> +       return NULL;
> +}
> +
> +static int fwft_get_feature(enum sbi_fwft_feature_t feature,
> +                           struct fwft_config **conf)
> +{
> +       int ret;
> +       struct fwft_config *tconf;
> +
> +       tconf = get_feature_config(feature);
> +       if (!tconf) {
> +               if (fwft_is_defined_feature(feature))
> +                       return SBI_ENOTSUPP;
> +
> +               return SBI_EDENIED;
> +       }
> +
> +       if (tconf->feature->supported) {
> +               ret = tconf->feature->supported(tconf);
> +               if (ret)
> +                       return ret;
> +       }
> +       *conf = tconf;
> +
> +       return SBI_SUCCESS;
> +}
> +
> +int sbi_fwft_set(enum sbi_fwft_feature_t feature, unsigned long value,
> +                unsigned long flags)
> +{
> +       int ret;
> +       struct fwft_config *conf;
> +
> +       ret = fwft_get_feature(feature, &conf);
> +       if (ret)
> +               return ret;
> +
> +       if ((flags & ~SBI_FWFT_SET_FLAG_LOCK) != 0)
> +               return SBI_ERR_INVALID_PARAM;
> +
> +       if (conf->flags & SBI_FWFT_SET_FLAG_LOCK)
> +               return SBI_EDENIED;
> +
> +       ret = conf->feature->set(conf, value);
> +       if (ret)
> +               return ret;
> +
> +       conf->flags = flags;
> +
> +       return SBI_OK;
> +}
> +
> +int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val)
> +{
> +       int ret;
> +       struct fwft_config *conf;
> +
> +       ret = fwft_get_feature(feature, &conf);
> +       if (ret)
> +               return ret;
> +
> +       return conf->feature->get(conf, out_val);
> +}
> +
> +static const struct fwft_feature features[] = {};
> +
> +int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
> +{
> +       int i;
> +       struct fwft_hart_state *fhs;
> +
> +       if (cold_boot) {
> +               fwft_ptr_offset = sbi_scratch_alloc_type_offset(void *);
> +               if (!fwft_ptr_offset)
> +                       return SBI_ENOMEM;
> +       }
> +
> +       fhs = fwft_get_hart_state_ptr(scratch);
> +       if (!fhs) {
> +               fhs = sbi_zalloc(sizeof(fhs) + array_size(features) * sizeof(struct fwft_config));
> +               if (!fhs)
> +                       return SBI_ENOMEM;
> +
> +               fhs->config_count = array_size(features);
> +               for (i = 0; i < array_size(features); i++)
> +                       fhs->configs[i].feature = &features[i];
> +
> +               fwft_set_hart_state_ptr(scratch, fhs);
> +       }
> +
> +       return 0;
> +}
> diff --git a/lib/sbi/sbi_init.c b/lib/sbi/sbi_init.c
> index 389172a..0f9e14c 100644
> --- a/lib/sbi/sbi_init.c
> +++ b/lib/sbi/sbi_init.c
> @@ -14,6 +14,7 @@
>  #include <sbi/sbi_cppc.h>
>  #include <sbi/sbi_domain.h>
>  #include <sbi/sbi_ecall.h>
> +#include <sbi/sbi_fwft.h>
>  #include <sbi/sbi_hart.h>
>  #include <sbi/sbi_hartmask.h>
>  #include <sbi/sbi_heap.h>
> @@ -308,6 +309,12 @@ static void __noreturn init_coldboot(struct sbi_scratch *scratch, u32 hartid)
>                 sbi_hart_hang();
>         }
>
> +       rc = sbi_fwft_init(scratch, true);
> +       if (rc) {
> +               sbi_printf("%s: fwft init failed (error %d)\n", __func__, rc);
> +               sbi_hart_hang();
> +       }
> +
>         /*
>          * Note: Finalize domains after HSM initialization so that we
>          * can startup non-root domains.
> @@ -423,6 +430,10 @@ static void __noreturn init_warm_startup(struct sbi_scratch *scratch,
>         if (rc)
>                 sbi_hart_hang();
>
> +       rc = sbi_fwft_init(scratch, false);
> +       if (rc)
> +               sbi_hart_hang();
> +
>         rc = sbi_platform_final_init(plat, false);
>         if (rc)
>                 sbi_hart_hang();
> --
> 2.45.2
>
>
> --
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi

[PATCH v3 2/4] lib: sbi: fwft: add support for SBI_FWFT_MISALIGNED_EXC_DELEG

[Anup Patel]

On Wed, Jun 19, 2024 at 3:13?PM Cl?ment L?ger <cleger@rivosinc.com> wrote:
>
> Add support for SBI_FWFT_MISALIGNED_EXC_DELEG withing FWFT support. This
> support allows to delegate misaligned accesses traps.
>
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>

LGTM.

Reviewed-by: Anup Patel <anup@brainfault.org>

Applied this patch to the riscv/opensbi repo.

Thanks,
Anup

> ---
>  lib/sbi/sbi_fwft.c | 39 ++++++++++++++++++++++++++++++++++++++-
>  lib/sbi/sbi_hsm.c  |  3 +++
>  2 files changed, 41 insertions(+), 1 deletion(-)
>
> diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
> index b302b5d..289a344 100644
> --- a/lib/sbi/sbi_fwft.c
> +++ b/lib/sbi/sbi_fwft.c
> @@ -32,6 +32,8 @@ static unsigned long fwft_ptr_offset;
>  #define fwft_set_hart_state_ptr(__scratch, __phs)                      \
>         sbi_scratch_write_type((__scratch), void *, fwft_ptr_offset, (__phs))
>
> +#define MIS_DELEG (1UL << CAUSE_MISALIGNED_LOAD | 1UL << CAUSE_MISALIGNED_STORE)
> +
>  struct fwft_config;
>
>  struct fwft_feature {
> @@ -71,6 +73,33 @@ static bool fwft_is_defined_feature(enum sbi_fwft_feature_t feature)
>         return false;
>  }
>
> +static int fwft_misaligned_delegation_supported(struct fwft_config *conf)
> +{
> +       if (!misa_extension('S'))
> +               return SBI_ENOTSUPP;
> +
> +       return SBI_OK;
> +}
> +
> +static int fwft_set_misaligned_delegation(struct fwft_config *conf,
> +                                        unsigned long value)
> +{
> +       if (value)
> +               csr_set(CSR_MEDELEG, MIS_DELEG);
> +       else
> +               csr_clear(CSR_MEDELEG, MIS_DELEG);
> +
> +       return SBI_OK;
> +}
> +
> +static int fwft_get_misaligned_delegation(struct fwft_config *conf,
> +                                        unsigned long *value)
> +{
> +       *value = (csr_read(CSR_MEDELEG) & MIS_DELEG) != 0;
> +
> +       return SBI_OK;
> +}
> +
>  static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
>  {
>         int i;
> @@ -148,7 +177,15 @@ int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val)
>         return conf->feature->get(conf, out_val);
>  }
>
> -static const struct fwft_feature features[] = {};
> +static const struct fwft_feature features[] =
> +{
> +       {
> +               .id = SBI_FWFT_MISALIGNED_EXC_DELEG,
> +               .supported = fwft_misaligned_delegation_supported,
> +               .set = fwft_set_misaligned_delegation,
> +               .get = fwft_get_misaligned_delegation,
> +       },
> +};
>
>  int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
>  {
> diff --git a/lib/sbi/sbi_hsm.c b/lib/sbi/sbi_hsm.c
> index be48d64..2b23e13 100644
> --- a/lib/sbi/sbi_hsm.c
> +++ b/lib/sbi/sbi_hsm.c
> @@ -44,6 +44,7 @@ struct sbi_hsm_data {
>         unsigned long suspend_type;
>         unsigned long saved_mie;
>         unsigned long saved_mip;
> +       unsigned long saved_medeleg;
>         atomic_t start_ticket;
>  };
>
> @@ -417,6 +418,7 @@ void __sbi_hsm_suspend_non_ret_save(struct sbi_scratch *scratch)
>
>         hdata->saved_mie = csr_read(CSR_MIE);
>         hdata->saved_mip = csr_read(CSR_MIP) & (MIP_SSIP | MIP_STIP);
> +       hdata->saved_medeleg = csr_read(CSR_MEDELEG);
>  }
>
>  static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
> @@ -424,6 +426,7 @@ static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
>         struct sbi_hsm_data *hdata = sbi_scratch_offset_ptr(scratch,
>                                                             hart_data_offset);
>
> +       csr_write(CSR_MEDELEG, hdata->saved_medeleg);
>         csr_write(CSR_MIE, hdata->saved_mie);
>         csr_set(CSR_MIP, (hdata->saved_mip & (MIP_SSIP | MIP_STIP)));
>  }
> --
> 2.45.2
>
>
> --
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi

[PATCH v3 3/4] lib: sbi: fwft: add support for SBI_FWFT_PTE_AD_HW_UPDATING

[Anup Patel]

On Wed, Jun 19, 2024 at 3:13?PM Cl?ment L?ger <cleger@rivosinc.com> wrote:
>
> Add support for SBI_FWFT_PTE_AD_HW_UPDATING based on SVADU presence.
>
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>

I had already reviewed the previous revision of this patch.

Reviewed-by: Anup Patel <anup@brainfault.org>

Applied this patch to the riscv/opensbi repo.

Thanks,
Anup

> ---
>  lib/sbi/sbi_fwft.c | 47 ++++++++++++++++++++++++++++++++++++++++++++++
>  lib/sbi/sbi_hsm.c  | 12 ++++++++++++
>  2 files changed, 59 insertions(+)
>
> diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
> index 289a344..aff087f 100644
> --- a/lib/sbi/sbi_fwft.c
> +++ b/lib/sbi/sbi_fwft.c
> @@ -100,6 +100,47 @@ static int fwft_get_misaligned_delegation(struct fwft_config *conf,
>         return SBI_OK;
>  }
>
> +static int fwft_adue_supported(struct fwft_config *conf)
> +{
> +       if (!sbi_hart_has_extension(sbi_scratch_thishart_ptr(),
> +                                   SBI_HART_EXT_SVADU))
> +               return SBI_ENOTSUPP;
> +
> +       return SBI_OK;
> +}
> +
> +static int fwft_set_adue(struct fwft_config *conf, unsigned long value)
> +{
> +       if (value)
> +#if __riscv_xlen == 32
> +               csr_set(CSR_MENVCFGH, ENVCFG_ADUE >> 32);
> +#else
> +               csr_set(CSR_MENVCFG, ENVCFG_ADUE);
> +#endif
> +       else
> +#if __riscv_xlen == 32
> +               csr_clear(CSR_MENVCFGH, ENVCFG_ADUE >> 32);
> +#else
> +               csr_clear(CSR_MENVCFG, ENVCFG_ADUE);
> +#endif
> +
> +       return SBI_OK;
> +}
> +
> +static int fwft_get_adue(struct fwft_config *conf, unsigned long *value)
> +{
> +       unsigned long cfg;
> +
> +#if __riscv_xlen == 32
> +       cfg = csr_read(CSR_MENVCFGH) & (ENVCFG_ADUE >> 32);
> +#else
> +       cfg = csr_read(CSR_MENVCFG) & ENVCFG_ADUE;
> +#endif
> +       *value = cfg != 0;
> +
> +       return SBI_OK;
> +}
> +
>  static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
>  {
>         int i;
> @@ -185,6 +226,12 @@ static const struct fwft_feature features[] =
>                 .set = fwft_set_misaligned_delegation,
>                 .get = fwft_get_misaligned_delegation,
>         },
> +       {
> +               .id = SBI_FWFT_PTE_AD_HW_UPDATING,
> +               .supported = fwft_adue_supported,
> +               .set = fwft_set_adue,
> +               .get = fwft_get_adue,
> +       },
>  };
>
>  int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
> diff --git a/lib/sbi/sbi_hsm.c b/lib/sbi/sbi_hsm.c
> index 2b23e13..7e32af3 100644
> --- a/lib/sbi/sbi_hsm.c
> +++ b/lib/sbi/sbi_hsm.c
> @@ -45,6 +45,10 @@ struct sbi_hsm_data {
>         unsigned long saved_mie;
>         unsigned long saved_mip;
>         unsigned long saved_medeleg;
> +       unsigned long saved_menvcfg;
> +#if __riscv_xlen == 32
> +       unsigned long saved_menvcfgh;
> +#endif
>         atomic_t start_ticket;
>  };
>
> @@ -419,6 +423,10 @@ void __sbi_hsm_suspend_non_ret_save(struct sbi_scratch *scratch)
>         hdata->saved_mie = csr_read(CSR_MIE);
>         hdata->saved_mip = csr_read(CSR_MIP) & (MIP_SSIP | MIP_STIP);
>         hdata->saved_medeleg = csr_read(CSR_MEDELEG);
> +#if __riscv_xlen == 32
> +       hdata->saved_menvcfgh = csr_read(CSR_MENVCFGH);
> +#endif
> +       hdata->saved_menvcfg = csr_read(CSR_MENVCFG);
>  }
>
>  static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
> @@ -426,6 +434,10 @@ static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
>         struct sbi_hsm_data *hdata = sbi_scratch_offset_ptr(scratch,
>                                                             hart_data_offset);
>
> +       csr_write(CSR_MENVCFG, hdata->saved_menvcfg);
> +#if __riscv_xlen == 32
> +       csr_write(CSR_MENVCFGH, hdata->saved_menvcfgh);
> +#endif
>         csr_write(CSR_MEDELEG, hdata->saved_medeleg);
>         csr_write(CSR_MIE, hdata->saved_mie);
>         csr_set(CSR_MIP, (hdata->saved_mip & (MIP_SSIP | MIP_STIP)));
> --
> 2.45.2
>
>
> --
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi

[PATCH v3 4/4] lib: sbi: implement SBI FWFT extension

[Anup Patel]

On Wed, Jun 19, 2024 at 3:13?PM Cl?ment L?ger <cleger@rivosinc.com> wrote:
>
> The SBI FWFT extension defines a set of function that can be called to
> control the configuration of some platform features (misaligned
> trap delegation, etc). This patch implements sbi_fwft_set() and
> sbi_fwft_get() as defined in the specification [1].
>
> Link: https://lists.riscv.org/g/tech-prs/message/924 [1]
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>

I had already reviewed the previous revision of this patch.

Reviewed-by: Anup Patel <anup@brainfault.org>

Applied this patch to the riscv/opensbi repo.

Thanks,
Anup

> ---
>  lib/sbi/Kconfig          |  4 ++++
>  lib/sbi/objects.mk       |  3 +++
>  lib/sbi/sbi_ecall_fwft.c | 49 ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 56 insertions(+)
>  create mode 100644 lib/sbi/sbi_ecall_fwft.c
>
> diff --git a/lib/sbi/Kconfig b/lib/sbi/Kconfig
> index cc8e031..6cf54ce 100644
> --- a/lib/sbi/Kconfig
> +++ b/lib/sbi/Kconfig
> @@ -38,6 +38,10 @@ config SBI_ECALL_CPPC
>         bool "CPPC extension"
>         default y
>
> +config SBI_ECALL_FWFT
> +       bool "Firmware Feature extension"
> +       default y
> +
>  config SBI_ECALL_LEGACY
>         bool "SBI v0.1 legacy extensions"
>         default y
> diff --git a/lib/sbi/objects.mk b/lib/sbi/objects.mk
> index 221e72c..211abad 100644
> --- a/lib/sbi/objects.mk
> +++ b/lib/sbi/objects.mk
> @@ -46,6 +46,9 @@ libsbi-objs-$(CONFIG_SBI_ECALL_DBCN) += sbi_ecall_dbcn.o
>  carray-sbi_ecall_exts-$(CONFIG_SBI_ECALL_CPPC) += ecall_cppc
>  libsbi-objs-$(CONFIG_SBI_ECALL_CPPC) += sbi_ecall_cppc.o
>
> +carray-sbi_ecall_exts-$(CONFIG_SBI_ECALL_FWFT) += ecall_fwft
> +libsbi-objs-$(CONFIG_SBI_ECALL_FWFT) += sbi_ecall_fwft.o
> +
>  carray-sbi_ecall_exts-$(CONFIG_SBI_ECALL_LEGACY) += ecall_legacy
>  libsbi-objs-$(CONFIG_SBI_ECALL_LEGACY) += sbi_ecall_legacy.o
>
> diff --git a/lib/sbi/sbi_ecall_fwft.c b/lib/sbi/sbi_ecall_fwft.c
> new file mode 100644
> index 0000000..267cbab
> --- /dev/null
> +++ b/lib/sbi/sbi_ecall_fwft.c
> @@ -0,0 +1,49 @@
> +/*
> + * SPDX-License-Identifier: BSD-2-Clause
> + *
> + * Copyright (c) 2024 Rivos Inc.
> + *
> + * Authors:
> + *   Cl?ment L?ger <cleger@rivosinc.com>
> + */
> +
> +#include <sbi/sbi_ecall.h>
> +#include <sbi/sbi_ecall_interface.h>
> +#include <sbi/sbi_error.h>
> +#include <sbi/sbi_fwft.h>
> +#include <sbi/sbi_trap.h>
> +
> +static int sbi_ecall_fwft_handler(unsigned long extid, unsigned long funcid,
> +                                struct sbi_trap_regs *regs,
> +                                struct sbi_ecall_return *out)
> +{
> +       int ret = 0;
> +
> +       switch (funcid) {
> +       case SBI_EXT_FWFT_SET:
> +               ret = sbi_fwft_set(regs->a0, regs->a1, regs->a2);
> +               break;
> +       case SBI_EXT_FWFT_GET:
> +               ret = sbi_fwft_get(regs->a0, &out->value);
> +               break;
> +       default:
> +               ret = SBI_ENOTSUPP;
> +               break;
> +       }
> +
> +       return ret;
> +}
> +
> +struct sbi_ecall_extension ecall_fwft;
> +
> +static int sbi_ecall_fwft_register_extensions(void)
> +{
> +       return sbi_ecall_register_extension(&ecall_fwft);
> +}
> +
> +struct sbi_ecall_extension ecall_fwft = {
> +       .extid_start = SBI_EXT_FWFT,
> +       .extid_end = SBI_EXT_FWFT,
> +       .register_extensions = sbi_ecall_fwft_register_extensions,
> +       .handle = sbi_ecall_fwft_handler,
> +};
> --
> 2.45.2
>
>
> --
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi

[PATCH v3 2/4] lib: sbi: fwft: add support for SBI_FWFT_MISALIGNED_EXC_DELEG

[Andrew Jones]

On Wed, Jun 19, 2024 at 11:42:40AM GMT, Cl?ment L?ger wrote:
> Add support for SBI_FWFT_MISALIGNED_EXC_DELEG withing FWFT support. This
> support allows to delegate misaligned accesses traps.
> 
> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
> ---
>  lib/sbi/sbi_fwft.c | 39 ++++++++++++++++++++++++++++++++++++++-
>  lib/sbi/sbi_hsm.c  |  3 +++
>  2 files changed, 41 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
> index b302b5d..289a344 100644
> --- a/lib/sbi/sbi_fwft.c
> +++ b/lib/sbi/sbi_fwft.c
> @@ -32,6 +32,8 @@ static unsigned long fwft_ptr_offset;
>  #define fwft_set_hart_state_ptr(__scratch, __phs)			\
>  	sbi_scratch_write_type((__scratch), void *, fwft_ptr_offset, (__phs))
>  
> +#define MIS_DELEG (1UL << CAUSE_MISALIGNED_LOAD | 1UL << CAUSE_MISALIGNED_STORE)
> +
>  struct fwft_config;
>  
>  struct fwft_feature {
> @@ -71,6 +73,33 @@ static bool fwft_is_defined_feature(enum sbi_fwft_feature_t feature)
>  	return false;
>  }
>  
> +static int fwft_misaligned_delegation_supported(struct fwft_config *conf)
> +{
> +	if (!misa_extension('S'))
> +		return SBI_ENOTSUPP;
> +
> +	return SBI_OK;
> +}
> +
> +static int fwft_set_misaligned_delegation(struct fwft_config *conf,
> +					 unsigned long value)
> +{
> +	if (value)
> +		csr_set(CSR_MEDELEG, MIS_DELEG);
> +	else
> +		csr_clear(CSR_MEDELEG, MIS_DELEG);

Sorry for my late review. This should be

  if (value == 1)
     csr_set(CSR_MEDELEG, MIS_DELEG);
  else if (value == 0)
     csr_clear(CSR_MEDELEG, MIS_DELEG);
  else
     return SBI_EINVAL;

It's unlikely we'll ever extend the inputs/behaviors, but if we don't
check for the inputs explicitly now, then we never can.

And same comment for SBI_FWFT_PTE_AD_HW_UPDATING.

Thanks,
drew

> +
> +	return SBI_OK;
> +}
> +
> +static int fwft_get_misaligned_delegation(struct fwft_config *conf,
> +					 unsigned long *value)
> +{
> +	*value = (csr_read(CSR_MEDELEG) & MIS_DELEG) != 0;
> +
> +	return SBI_OK;
> +}
> +
>  static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
>  {
>  	int i;
> @@ -148,7 +177,15 @@ int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val)
>  	return conf->feature->get(conf, out_val);
>  }
>  
> -static const struct fwft_feature features[] = {};
> +static const struct fwft_feature features[] =
> +{
> +	{
> +		.id = SBI_FWFT_MISALIGNED_EXC_DELEG,
> +		.supported = fwft_misaligned_delegation_supported,
> +		.set = fwft_set_misaligned_delegation,
> +		.get = fwft_get_misaligned_delegation,
> +	},
> +};
>  
>  int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
>  {
> diff --git a/lib/sbi/sbi_hsm.c b/lib/sbi/sbi_hsm.c
> index be48d64..2b23e13 100644
> --- a/lib/sbi/sbi_hsm.c
> +++ b/lib/sbi/sbi_hsm.c
> @@ -44,6 +44,7 @@ struct sbi_hsm_data {
>  	unsigned long suspend_type;
>  	unsigned long saved_mie;
>  	unsigned long saved_mip;
> +	unsigned long saved_medeleg;
>  	atomic_t start_ticket;
>  };
>  
> @@ -417,6 +418,7 @@ void __sbi_hsm_suspend_non_ret_save(struct sbi_scratch *scratch)
>  
>  	hdata->saved_mie = csr_read(CSR_MIE);
>  	hdata->saved_mip = csr_read(CSR_MIP) & (MIP_SSIP | MIP_STIP);
> +	hdata->saved_medeleg = csr_read(CSR_MEDELEG);
>  }
>  
>  static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
> @@ -424,6 +426,7 @@ static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
>  	struct sbi_hsm_data *hdata = sbi_scratch_offset_ptr(scratch,
>  							    hart_data_offset);
>  
> +	csr_write(CSR_MEDELEG, hdata->saved_medeleg);
>  	csr_write(CSR_MIE, hdata->saved_mie);
>  	csr_set(CSR_MIP, (hdata->saved_mip & (MIP_SSIP | MIP_STIP)));
>  }
> -- 
> 2.45.2
> 
> 
> -- 
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi

[PATCH v3 2/4] lib: sbi: fwft: add support for SBI_FWFT_MISALIGNED_EXC_DELEG

[Clément Léger]

On 21/06/2024 15:50, Andrew Jones wrote:
> On Wed, Jun 19, 2024 at 11:42:40AM GMT, Cl?ment L?ger wrote:
>> Add support for SBI_FWFT_MISALIGNED_EXC_DELEG withing FWFT support. This
>> support allows to delegate misaligned accesses traps.
>>
>> Signed-off-by: Cl?ment L?ger <cleger@rivosinc.com>
>> ---
>>  lib/sbi/sbi_fwft.c | 39 ++++++++++++++++++++++++++++++++++++++-
>>  lib/sbi/sbi_hsm.c  |  3 +++
>>  2 files changed, 41 insertions(+), 1 deletion(-)
>>
>> diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
>> index b302b5d..289a344 100644
>> --- a/lib/sbi/sbi_fwft.c
>> +++ b/lib/sbi/sbi_fwft.c
>> @@ -32,6 +32,8 @@ static unsigned long fwft_ptr_offset;
>>  #define fwft_set_hart_state_ptr(__scratch, __phs)			\
>>  	sbi_scratch_write_type((__scratch), void *, fwft_ptr_offset, (__phs))
>>  
>> +#define MIS_DELEG (1UL << CAUSE_MISALIGNED_LOAD | 1UL << CAUSE_MISALIGNED_STORE)
>> +
>>  struct fwft_config;
>>  
>>  struct fwft_feature {
>> @@ -71,6 +73,33 @@ static bool fwft_is_defined_feature(enum sbi_fwft_feature_t feature)
>>  	return false;
>>  }
>>  
>> +static int fwft_misaligned_delegation_supported(struct fwft_config *conf)
>> +{
>> +	if (!misa_extension('S'))
>> +		return SBI_ENOTSUPP;
>> +
>> +	return SBI_OK;
>> +}
>> +
>> +static int fwft_set_misaligned_delegation(struct fwft_config *conf,
>> +					 unsigned long value)
>> +{
>> +	if (value)
>> +		csr_set(CSR_MEDELEG, MIS_DELEG);
>> +	else
>> +		csr_clear(CSR_MEDELEG, MIS_DELEG);
> 
> Sorry for my late review. This should be
> 
>   if (value == 1)
>      csr_set(CSR_MEDELEG, MIS_DELEG);
>   else if (value == 0)
>      csr_clear(CSR_MEDELEG, MIS_DELEG);
>   else
>      return SBI_EINVAL;
> 
> It's unlikely we'll ever extend the inputs/behaviors, but if we don't
> check for the inputs explicitly now, then we never can.
> 
> And same comment for SBI_FWFT_PTE_AD_HW_UPDATING.

Arg, I thought I had this right but I might have dropped it at some
point. But agreed this needs to be checked thoroughly. I'll send a fix.

Thanks,

Cl?ment

> 
> Thanks,
> drew
> 
>> +
>> +	return SBI_OK;
>> +}
>> +
>> +static int fwft_get_misaligned_delegation(struct fwft_config *conf,
>> +					 unsigned long *value)
>> +{
>> +	*value = (csr_read(CSR_MEDELEG) & MIS_DELEG) != 0;
>> +
>> +	return SBI_OK;
>> +}
>> +
>>  static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
>>  {
>>  	int i;
>> @@ -148,7 +177,15 @@ int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val)
>>  	return conf->feature->get(conf, out_val);
>>  }
>>  
>> -static const struct fwft_feature features[] = {};
>> +static const struct fwft_feature features[] =
>> +{
>> +	{
>> +		.id = SBI_FWFT_MISALIGNED_EXC_DELEG,
>> +		.supported = fwft_misaligned_delegation_supported,
>> +		.set = fwft_set_misaligned_delegation,
>> +		.get = fwft_get_misaligned_delegation,
>> +	},
>> +};
>>  
>>  int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
>>  {
>> diff --git a/lib/sbi/sbi_hsm.c b/lib/sbi/sbi_hsm.c
>> index be48d64..2b23e13 100644
>> --- a/lib/sbi/sbi_hsm.c
>> +++ b/lib/sbi/sbi_hsm.c
>> @@ -44,6 +44,7 @@ struct sbi_hsm_data {
>>  	unsigned long suspend_type;
>>  	unsigned long saved_mie;
>>  	unsigned long saved_mip;
>> +	unsigned long saved_medeleg;
>>  	atomic_t start_ticket;
>>  };
>>  
>> @@ -417,6 +418,7 @@ void __sbi_hsm_suspend_non_ret_save(struct sbi_scratch *scratch)
>>  
>>  	hdata->saved_mie = csr_read(CSR_MIE);
>>  	hdata->saved_mip = csr_read(CSR_MIP) & (MIP_SSIP | MIP_STIP);
>> +	hdata->saved_medeleg = csr_read(CSR_MEDELEG);
>>  }
>>  
>>  static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
>> @@ -424,6 +426,7 @@ static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
>>  	struct sbi_hsm_data *hdata = sbi_scratch_offset_ptr(scratch,
>>  							    hart_data_offset);
>>  
>> +	csr_write(CSR_MEDELEG, hdata->saved_medeleg);
>>  	csr_write(CSR_MIE, hdata->saved_mie);
>>  	csr_set(CSR_MIP, (hdata->saved_mip & (MIP_SSIP | MIP_STIP)));
>>  }
>> -- 
>> 2.45.2
>>
>>
>> -- 
>> opensbi mailing list
>> opensbi at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/opensbi